How to make an alpine trough

You will need

Bricks
Coir fibre
Cement
Plastic sheet
Sand
Trowel
Two cardbaord boxes
Wire mesh
Wooden dowel

Do it: spring to autumn

Takes just: a couple of hours, then two days to let the concrete set

Project categories

Overview

Old stone sinks make perfect containers for alpines, but they're hard to come by. You can easily make your own concrete lookalike; all you need are two strong cardboard boxes. One should fit inside the other, leaving a gap of around 5cm. Simply make a mould from the cardboard boxes and fill it with a concrete mix. Adding coir to the concrete mix will give your container a rougher texture, and the trough can be easily distressed with a trowel to give it a more aged appearance.

How to do it

Mix together two parts sieved coir fibre, one part cement and one part sharp sand. Pour water into a well in the centre and mix it together to form a stiff paste.

Using a trowel, place a 2.5cm layer of concrete into the bottom of the larger cardboard box. Ensure the concrete is spread into the corners.

Adding wire mesh to the base of the trough

Cut a piece of small-gauge wire mesh to fit the bottom of the box. Place it on top of the mixture to reinforce the trough, and add a further 2.5cm layer of cement over the top of the mesh.

Push 5cm-long pieces of wooden dowel into the base of the trough for drainage. Then, place the smaller box inside the larger one, leaving a gap of around 5cm.

Adding bricks and more wire mesh to reinforce the walls

Putting bricks inside the inner box will stop it collapsing. Insert sections of mesh along each side, cutting them shorter than the depth of the box so they'll be hidden.

Add cement to the sides of the mould to make a wall. Use a stick to push it into the corners. This will prevent air pockets from weakening the walls.

Adding bricks to the side of the box to support it

When all the concrete mixture is in place, support the outer sides of the box with more bricks. Then cover the entire thing with a plastic sheet.

After two days, when the concrete is set, remove the sheet of plastic and supporting bricks and peel the cardboard away from the sides.

The sides of the trough can be aged by roughly scraping them with a trowel. After a week, use a hammer and large nail to push the wooden dowels out of the trough, leaving holes for drainage.